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INTRODUCTION

Schwannomas that arise within the muscle plane are called intramuscular schwannomas. The low incidence of these tumours and the lack of specific clinical features make preoperative diagnosis difficult. Herein, we report our experience with intramuscular schwannomas. We present details of the clinical presentation, radiological diagnosis and management of these tumours.

METHODS

Between January 2011 and December 2013, 29 patients were diagnosed and treated for histologically proven schwannoma at the National University Hospital, Singapore. Among these 29 patients, eight (five male, three female) had intramuscular schwannomas.

RESULTS

The mean age of the eight patients was 40 (range 27–57) years. The most common presenting feature was a palpable mass. The mean interval between surgical treatment and the onset of clinical symptoms was 17.1 (range 4–72) months. Six of the eight tumours (75.0%) were located in the lower limb, while 2 (25.0%) were located in the upper limb. None of the patients had any preoperative neurological deficits. Tinel’s sign was present in one patient. Magnetic resonance (MR) imaging showed that the findings of split-fat sign, low signal margin and fascicular sign were present in all patients. The entry and exit sign was observed in 4 (50.0%) patients, a hyperintense rim was observed in 7 (87.5%) patients and the target sign was observed in 5 (62.5%) patients. All patients underwent microsurgical excision of the tumour and none developed any postoperative neurological deficits.

CONCLUSION

Intramuscular schwannomas demonstrate the findings of split-fat sign, low signal margin and fascicular sign on MR imaging. These findings are useful for the radiological diagnosis of intramuscular schwannoma.  相似文献   
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Gallbladder metastases are very rare and usually arise from malignant melanoma, renal cell carcinoma and cervical carcinoma. Breast carcinoma tnetastatic to the gallbladder is extremely rare and only 4 cases have been reported in the English literature. We hereby report a 54-year-old lady who was diagnosed as having breast carcinoma and underwent modified radical mastectomy. One month after the operation, she developed acute abdomenal pain and underwent cholecystectomy after clinical investigation. Histopathological examination revealed metastasis to the gallbladder. Being considered a patient with tnetastatic breast carcinoma she was subjected to taxane and anthracycline-based palliative chemotherapy. Later she had CNS involvement and died of the progressive disease soon after few months.  相似文献   
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IQGAPs genes play critical role in either induction or suppression of cancer and its progression, however the relationship between Ras genes and these genes are still unclear. In this study, we tried to understand the mechanistic action of IQGAPs genes and its correlation with Ras genes in mouse hepatic cancer model. The genetic expressions of IQGAP1, IQGAP2, IQGAP3, Hras, Kras, Nras, Mras, Caspase3, and BAX were followed in both hepatocellular carcinoma and normal liver cells of Balbc mice. Genotoxic agent diethylnitrosamine (DEN)-induced hepatic cancer model was induced in male mice and recorded the occurrence of hepatocellular carcinoma by morphological and histological changes in the liver. It was observed that mRNA expressions of IQGAP1, Hras, Kras, Nras, Mras, Caspase3, and BAX genes were highly elevated in hepatocellular carcinoma cells when compared with normal liver cells, additionally their expressions increased by concentrating the dose of DEN. While, the expressions of IQGAP2 and IQGAP3 were significantly decreased in hepatocellular carcinoma cells when compared with normal liver cells, as well as their expressions decreased more with increasing the dose of DEN. It was concluded from this study that IQGAP1 has a strong signaling relationship with Ras genes in induction of cancer and it is considered as a key gene for induction or suppression of the hepatocellular carcinoma.  相似文献   
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A new fluorescent sensor 5 based on a fused imidazopyridine scaffold has been designed and synthesized via cascade cyclization. The reaction features the formation of three different C–N bonds in sequence. Imidazopyridine based fluorescent probe 5 exhibits highly sensitive and selective fluorescent sensing for Fe3+(‘turn-on’) and Hg2+(‘turn-off’). The excellent selectivity of imidazopyridine for Fe3+/Hg2+ was not hampered in the presence of any of the competing cations. The limit of detection (LOD) of 5 toward Fe3+ and Hg2+ has been estimated to be 4.0 ppb and 1.0 ppb, respectively, with a good linear relationship (R2 = 0.99). Notably, 5 selectively detects Fe3+/Hg2+ through fluorescence enhancement signalling both in vitro and in HeLa cells.

A new fluorescent sensor 5 having fused imidazopyridine scaffold has been synthesized via cascade cyclization. It exhibits highly sensitive and selective detection of Fe3+ (‘turn-on’) and Hg2+ (‘turn-off’) in vitro and in HeLa cells.  相似文献   
99.
Serum ferritin levels of low birth weight (LBW; BW?<?2,500 g) and normal birth weight (NBW; BW?≥?2,500 g) infants were evaluated at birth and at 3 mo using electrochemiluminescence immunoassay. At birth, levels were 318.6 (31.0–829.5) ng/mL in LBW (n?=?217) and 366.2 (122.4–858.5) ng/mL in NBW infants (n?=?116; p?<?0.01), with 1.4 % of LBW and none of the NBW infants having levels <12 ng/mL (p?=?0.20). At follow up, levels were 66.9 (4.5–567.7) ng/mL in LBW (n?=?126) and 126.2 (6.8–553.7) ng/mL in NBW infants (n?=?76; p?=?0.27), with 11.9 % of LBW and 11.8 % of NBW infants having levels <12 ng/mL (p?=?0.80).  相似文献   
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